Global internet protocol (IP) traffic has quadrupled over the past five years and will likely sustain that pace. Growth in network bandwidth demand could soon outpace the telecommunication industry's ability to deliver. Recent increases in bandwidth demand are due largely to the advent of mobile internet devices, such as smartphones and tablet computers. Compounding the growing number of mobile internet devices, which will soon outnumber the people on Earth, is the fact that video constitutes a majority of the IP traffic. Video streaming consumes significantly larger amounts of bandwidth than typical file sharing and audio.
Bandwidth scarcity is a pressing problem for the telecommunication industry. While some industry players wrestle with the technology to expand network bandwidth, others focus on making existing networks and devices more efficient. RoHC is a standardized method of compressing IP, user datagram protocol (UDP), UDP-Lite, real-time transport protocol (RTP) and transmission control protocol (TCP) headers of internet, or “network packets.” Network packets are formatted units of data transmitted and received over a network. Each packet carries data, which is sometimes referred to as payload or user data, and a header, which contains control data. The header portion of a network packet is essentially the overhead associated with transmitting and receiving that one packet. The control data is necessary for the network to deliver the user data and includes source and destination addresses, error detection data, timestamps and other fields.
RoHC takes advantage of information redundancies in the packet headers by transmitting redundant information once at the beginning of a data flow and only variable information from then on. For example, given a data flow between a source and a destination, the source and destination addresses need only be transmitted once, when the data flow initiates. The bytes allocated to the source and destination addresses are omitted from subsequent packet headers. A RoHC compressor converts the large packet headers into smaller, compressed packet headers before transmission and receipt. A RoHC decompressor at the receiver reconstructs the original packet headers from the received compressed packet headers.